An NH4I-promoted and H2O-controlled intermolecular difunctionalization of alkenes for the synthesis of bis-methylsulfane and beta-hydroxysulfides is presented. Mechanistic investigation revealed the reaction proceeds via methylthiyl radical addition to C=C of alkenes to give a carbon-centered radical and immediately cyclize to a thiiranium ion, followed by combination with H2O to afford beta-hydroxysulfides in 52-89% yields with chemo- and regioselectivities. In the absence of water, 1,2-disulfenylation takes place to give bis-methylsulfane in moderate to good yields.
Reaction of thiolsulfinates with trihaloacetic anhydrides. II
various olefins in carbon tetrachloride afforded the corresponding β-trifluoro- or trichloroacetoxy sulfides in good yields. The β-trihaloacetoxy sulfides are considered to be resulted by the electrophilic addition of the sulfenyl trihaloacetates, formed as transient intermediates, to olefins. The addition takes place stereospecifically in trans manner and the regioselectivity for the addition with unsymmetrical